From 4141746f8f3851f6f93c6185b0f17856aa0bf83a Mon Sep 17 00:00:00 2001
From: John Sully <john@csquare.ca>
Date: Fri, 6 May 2022 16:29:27 +0000
Subject: [PATCH] Fix crash in save of masterinfo

---
 src/rdb.cpp  | 2 ++
 src/server.h | 3 ++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/rdb.cpp b/src/rdb.cpp
index 9c74914d2..73f89e76e 100644
--- a/src/rdb.cpp
+++ b/src/rdb.cpp
@@ -1222,6 +1222,8 @@ int rdbSaveInfoAuxFields(rio *rdb, int rdbflags, rdbSaveInfo *rsi) {
             sdsstring val = sdsstring(sdsempty());
 
             for (auto &msi : rsi->vecmastersaveinfo) {
+                if (msi.masterhost == nullptr)
+                    continue;
                 val = val.catfmt("%s:%I:%s:%i:%i;", msi.master_replid,
                     msi.master_initial_offset,
                     msi.masterhost.get(),
diff --git a/src/server.h b/src/server.h
index 386f8e754..e17390c90 100644
--- a/src/server.h
+++ b/src/server.h
@@ -1904,7 +1904,8 @@ struct MasterSaveInfo {
             selected_db = 0;
         }
         masterport = mi.masterport;
-        masterhost = sdsstring(sdsdup(mi.masterhost));
+        if (mi.masterhost)
+            masterhost = sdsstring(sdsdup(mi.masterhost));
         masterport = mi.masterport;
     }